Last month, Jennifer Cunningham, the veteran Albany lobbyist who represented the state’s behemoth health-care union, announced she was resigning from her high-powered firm.

Cunningham — one of Gov.-elect Cuomo’s closest friends and advisors and the ex-wife of incoming Attorney General Eric Schneiderman — said her personal relationships with the state’s two top executives were carrying her into murky legal water.

“I wasn’t willing to risk having everyone question my motives,” Cunningham told The Post. “There’s a perception that I’m close with Cuomo — and I am. I don’t want him and I don’t want Eric to have someone alleging that they did or didn’t do something because of me. For everyone’s sake, I can go do something else with my life.”

But by appearing to step back, Cunningham, 48, has positioned herself to become even more influential.

“I expect her calls to be returned quicker than ever,” said Kevin Sheekey, a former top Bloomberg aide who now runs government relations for Bloomberg L.P. “If Cuomo and Schneiderman are turning to one person, they’re turning to her, and have turned to her in the past, and will turn to her in the future. If either of them are asked who they would rely on most for political advice publicly and privately, it’s Jennifer.”

Cunningham is widely considered the most influential woman in Cuomo’s tight circle, someone he asks for advice on everything from political calculations to staffing decisions.

Her unclassified role in his incoming administration has some resemblances to that of Patti Harris, Mayor Bloomberg’s most loyal and long-serving deputy, whose ubiquitous influence in Bloomberg’s administration defy any clear job title.

So, what will Cunningham be whispering into the ears of power?

Her background as the former executive vice president and lead lobbyist for the health-care union, 1199 SEIU, makes her the obvious liaison between Cuomo and the union. Cuomo has reportedly already reached out to the SEIU to discuss out-of-control Medicaid spending in order to avoid a bruising public battle.

Cuomo is “very focused on the home health-care community,” Cunningham said. “There’s no way to get your hands around a $9 billion problem without looking at a substantial reduction and reorganization of the Medicaid program.”

Insiders said they expect Cunningham to grease the wheels she punctured for former Gov. Eliot Spitzer in 2007, when she helped launch an aggressive $12 million ad campaign to attack his proposed $1.29 billion in Medicaid cuts.

“With Jennifer gone [as a lobbyist], they need her more than ever,” Sheekey said.

Cunningham said she will continue doing consulting work for the union. “To the extent that they’re figuring out what they’re going to do in Albany, I can give them my two cents,” she said.

But as for a broader political framework, colleagues describe Cunningham as more of a pragmatist than a progressive.

“She’s liberal and progressive by nature and background, but her guiding principles are pragmatic in terms of what she has to do to get something done in Albany,” said veteran Republican lobbyist James Featherstonhaugh, who points out that she forged a close relationship with former Republican Senate Majority Leader Joe Bruno.

Cunningham is circumspect about how she’ll use her closeness to Cuomo to influence state policy.

“I’m going to be a friend,” is all she offers about her role. “I was primarily a friend [during the election], and if he wanted advice from me I would offer it. I’m more than happy to be helpful in any way I can be, but it’s up to the governor-elect.”

In a statement, Cuomo called Jennifer “one of the top political minds in the business. She’s smart, strategic, tough and honest.”

But generic praise downplays their close bond.

Political insiders said Cunningham would have been on the short list for the most powerful post in the administration, secretary to the governor. But it was a financial decision and a question of timing that she chose to continue to influence from outside rather than from within the administration.

“I didn’t even pursue it because of personal reasons,” said Cunningham, whose daughter is leaving for college next fall. If the timing had been different, “working in the administration would have been something I would have considered.”

Cunningham’s significant influence is a result, in part, of simply being around Albany for almost as long as the abiding Assembly Speaker Shelly Silver (she once served as his counsel) and knowing everyone in the game.

Cunningham arrived in Albany the first week in January 1983, a fresh-faced 21-year-old Wesleyan University grad, with the unsexy title of legislative intern in the Political Action Department of District Council 37.

At the time, 26-year-old Andrew Cuomo was working for his father, newly elected Gov. Mario Cuomo, and the two became friends.

As for her influence over Schneiderman, insiders said her presence during his AG campaign was “constant” and that they’ve never seen such a functionally divorced couple.

“We’ve always been good friends,” Cunningham said of her ex-husband, who lives close to her on the Upper West Side and shares custody of their daughter, Catherine, a high school senior. “Especially with a kid in the mix, he’s family. he’s always going to be Catherine’s dad.”

For now, Cunningham is playing her cards close to the vest, downplaying her unique position as the nexis of many, sometimes competing state interests. And longtime colleagues said they don’t expect that to change.

“You can’t outwork her or outsmart her and only rarely outmaneuver her,” Featherstonhaugh said. “I’ve never heard her discuss politics after a third drink.”